Jon Rahm believes the challenge of Oakmont this week is set to provide players with "one of the truest representations of what the U.S. Open is all about".

Rahm, who won the title in 2021, has been far from his best at major championships after his announcement in December 2023 that he would be joining LIV Golf. 

In his first start at a major as a member of LIV, the Spaniard tied for 45th at the 2024 Masters, narrowly avoiding the cut and has rarely improved in recent tournaments. 

The 125th edition of the U.S. Open is taking place at Oakmont, a course where Rahm made his first appearance at a major back in 2016, where he finished T-23rd. 

Winner at Torrey Pines in 2021, he will aim to be only the third non-US golfer to win multiple U.S. Opens over the last 100 years, after South Africans Ernie Els and Retief Goosen.

However, the 30-year-old is bracing for a difficult week amid deep rough and fast greens around the course. 

"I mean, in theory, same as any other, but you're aware of what a golf tournament here is going to be like, it's going to be a challenge," Rahm said of his own mindset. 

"A lot of unfortunate things are going to happen. It's hard fairways to hit, bad lies, difficult bunkers, difficult greens. 

"It's going to be a nice test, a difficult test. And I think one of the truest representations of what a US Open is all about."

World number one Scottie Scheffler, who has won 16 PGA Tour events since the start of 2022, is among the favourites to win the title this weekend. 

But the American will expect a challenge from Bryson DeChambeau, who is aiming to become the fourth golfer since World War Two to win back-to-back U.S. Open tournaments.

And Rahm believes the tournament could be won with a final score over par, saying: "It's just a tough course. It's so difficult that very few times anybody has won under par.

"If it doesn't rain, most likely over par will win again. It's something that none of us, I would say, are used to, but it's a challenge you need to embrace.

"If there's any part of your game that will be tested on a week like this, it will be your mental game, that's for sure."

Rahm's group for the first two rounds of the U.S. Open was revealed on Tuesday, and he is joined by former world number ones Dustin Johnson and Jordan Spieth.